1641720510197 has 2 divisors, whose sum is σ = 1641720510198. Its totient is φ = 1641720510196.

The previous prime is 1641720510173. The next prime is 1641720510253. The reversal of 1641720510197 is 7910150271461.

It is a weak prime.

It can be written as a sum of positive squares in only one way, i.e., 1552817546641 + 88902963556 = 1246121^2 + 298166^2 .

It is a cyclic number.

It is not a de Polignac number, because 1641720510197 - 2³² = 1637425542901 is a prime.

It is a congruent number.

It is not a weakly prime, because it can be changed into another prime (1641720510497) by changing a digit.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 820860255098 + 820860255099.

It is an arithmetic number, because the mean of its divisors is an integer number (820860255099).

Almost surely, 2^{1641720510197} is an apocalyptic number.

It is an amenable number.

1641720510197 is a deficient number, since it is larger than the sum of its proper divisors (1).

1641720510197 is an equidigital number, since it uses as much as digits as its factorization.

1641720510197 is an odious number, because the sum of its binary digits is odd.

The product of its (nonzero) digits is 105840, while the sum is 44.

The spelling of 1641720510197 in words is "one trillion, six hundred forty-one billion, seven hundred twenty million, five hundred ten thousand, one hundred ninety-seven".